Taiwanese LED package company Everlight and Japanese LED producer Nichia have continued their dispute regarding the patent of YAG. On October 1st 2018, the Supreme Court of the United State has confirmed the invalidity of Nichia’s assertions about its YAG patents.

Everlight has filed a declaratory judgment action against Nichia for invalidity and non-infringement of U.S. Patent No. 5,998,925 and 7,531,960 in the U.S. District Court for the Eastern District of Michigan in April 2012. These two patents are related to the YAG phosphors being used in LEDs and phosphor concentration. The District Court found all of Nichia’s asserted claims to be invalid. Nichia then appealed to United States Court of Appeals for the Federal Circuit (CAFC), but in March 30, 2018, CAFC again confirmed the patent’s invalidity. Afterwards, Nichia appealed to the Supreme Court of the United State and its patents were confirmed invalid in October, 2018.

The patent dispute between the two companies also took place in Germany. In July 2018, the German Federal Patent Court confirmed the validity of Nichia’s YAG patent and rejected the nullity action of Everlight. The judgment of the Federal Patent Court is not final and can still be appealed.